The nails of many animals, including humans, are an excellent place for parasites, fungi, and other organisms to thrive. Nails provide an excellent place for these organisms to live because these organisms can be difficult to remove due to the difficulty and pain involved with removing said organisms from these areas. Of the aforementioned organisms, many types of fungi thrive particularly well in these environments. One such fungus is Trichophyton rubrum (“T. rubrum”)—the most common cause of athlete's foot, jock itch, and ringworm.
Further, T. rubrum accounts for approximately 80% of cases of onychomycosis, a chronic condition caused by infection of a person's nail and nail bed. Onychomycosis is a fungal infection of the toenails or fingernails that may involve any component of the nail unit, including the matrix, bed, or plate. Onychomycosis can cause pain, discomfort, and disfigurement in the nail and nail bed. Further, it may produce serious physical and occupational limitations, as well as reducing quality of life. In extreme cases, such as infections in patients with diabetes, onychomycosis can result in the loss of a digit.
Today, there are various estimates as to the prevalence of onychomycosis, but in the western world infection rates of up to 18% of the adult population have been cited. For people over age 60, the prevalence is 30% and the prevalence rate of onychomycosis is thought to be even higher in people with diabetes. As these ailments still afflict a large percentage of the world's population, logic dictates that even with modern technology, the field of nail fungus treatment leaves room for improvement.
One method for treating nail fungus is the use of topical agents. Throughout the history of onychomycosis and other nail and nail bed infections, many people have stated a preference for this type of treatment. These techniques do have some positive effect on onychomycosis; however topical agents are unable to penetrate the hyperkeratotic nail plate, which renders them incapable of fully eliminating a serious infection. Treatment using nail avulsion in combination with topical therapy has been somewhat more successful than topical ointment alone, but this approach can be time-consuming, temporarily disabling, and painful. Ciclopirox (Penlac) is an example of a topical agent, which is applied as a liquid or as a lacquer on the nail, for the treatment of mild to moderate onychomycosis caused by T. rubrum without involvement of the lunula. Although safe and relatively inexpensive, ciclopirox therapy is seldom effective. Newer topical agents include terbinafine (Lamisil®), itraconazole (Sporanox®), and fluconazole (Diflucan®). Terbinafine and itraconazole therapies are widely accepted while fluconazole is rapidly gaining acceptance in the market as topical and oral agents.
These new medications share characteristics that enhance their effectiveness: prompt penetration of the nail and nail bed, persistence in the nail for months after discontinuation of therapy and generally good safety profiles. Although published studies indicate good efficacy for these treatments, particularly with the oral forms of these agents when used to treat onychomycosis, the length of the treatments is equal to the time it takes for the nail to grow out, which is typically 4-9 months. Further, the associated side effects of these new drugs make them very unattractive for many potential users.
These pharmaceutical compounds exert their effect by inhibiting and halting the growth of the causative fungal organisms. While this method has also proved effective, ingesting these pharmaceutical compounds has proven to be toxic to a user's liver, and frequently results in expensive and burdensome monitoring of a patient's blood chemistry.
Current systems that are used to treat such nail fungi often employ either Class 3R or Class 4R lasers. One such laser is a Nd:YAG laser which produces burst of short pulses of laser light at 1064 nm. These bursts of light raise the temperature of the fungal hyphae, through selective absorption, the main mode of vegetative growth for fungi. If a temperature of 65° C. (149° F.) is maintained for 7 seconds, this is sufficient to denature the proteins of the fungi and cause permanent damage to the fungi. The light absorption is selective, which means that the temperature of the nail bed does not exceed 45° C. (113° F.) during the treatment and causes no damage to healthy tissue. These systems are highly effective at removing the fungi, however, they often cause pain to the receiver of the treatment. This pain is caused by the body of the receiver of treatment absorbing a large percentage of the laser's light, resulting in an increase in temperature which leads to pain. This means that whenever a patient wants to get their nail fungus removed via laser, they will have to experience great pain.
Thus, there is a need for a method and apparatus for an effective treatment of nail fungi that does not cause the user pain, does not subject the user to any potential harm, and does not result in the user incurring any undue expense.
There have been developments in anti-fungal treatments using Low Level Laser Therapy (“LLLT”). The attraction of this type of device is the inherent safety of the wavelengths in the near infrared and the low levels of energy and consequently lower temperatures used in the treatment. In addition, unlike Photodynamic Therapy (PDT), there is no requirement for a photosensitising agent. PDT has been proposed by many as a possible treatment for onychomycosis, but getting the photosensitising agent through the nail into the nail bed poses a significant challenge. The process of photodamage to the fungal hyphae using LLLT is a very complex one and not entirely understood, although there is clinical evidence to support its use. In a 1999 study by Neuman, it was discovered that two peaks at 870 nm and 930 nm in caused significant photodamage to E. coli. See Neuman et al., Characterization of Photodamage to Escherichia coli in Optical Traps, Biophysical Journal 77, November 1999.
Since then, the most notable development in this field is the Noveon laser produced by Nomir Technologies, Incorporated. The Noveon is a laser diode system which operates at two wavelengths—870 nm and 930nm—both of which have been shown to demonstrate anti-fungal properties. Several studies have been carried out, the most significant being by Landsman. There, a 180-day study of the effects of theses wavelengths on the treatment of onychomycosis. See Landsman, et al. Treatment of Mild, Moderate, and Severe Onychomycosis Using 870- and 930-nm Light Exposure, Journal of the American Podiatric Medical Association, 100(3), May/June 2010. A subsequent 270-day follow up was also carried out. These studies demonstrated the selectiveness of these wavelengths to negatively affect only fungi and bacteria, not mammalian cells. The claimed embodiments are directed towards a method and apparatus capable of exploiting these phenomena to provide a safe and effective way to cure onychomycosis.
Review of Related Technology:
United States Patent Application Publication Number 2012/0283622 pertains to a dermatological treatment device primarily suitable for treating nail fungus. This publication discloses the use of a photochemically active substance, effectively controlling the fungus by irradiating it with light at a wavelength that has no ancillary effects on the patient's health. It is possible to use either a gas discharge lamp or light emitting diodes as an appropriate light source for the claimed method and apparatus. Preferably, a transparent shoe-shaped optical shielding housing that absorbs short-wave light is used.
U.S. Pat. No. 7,306,620 pertains to a method for the prevention and treatment of microbial infections that occur on, or just below, the skin and nails of a person. The treatment consists of irradiating an area of the skin and nails for a period of time long enough to kill the organisms causing the infection. Additionally, some optional features increase the safety of the treatment. These options achieve this by shielding non-infected areas from irradiation, and including a cover to prevent damage to sight which may result from viewing the electromagnetic radiation.
United States Patent Application Publication Number 2005/0256552 pertains to a battery-powered toenail fungus eradicator that can be comfortably worn while sleeping. Alternatively, this device can be worn continuously.
U.S. Pat. No. 5,616,140 pertains to a method and apparatus for therapeutic laser treatment. The apparatus comprises a portable, battery-operated, laser bandage having a plurality of hyper-red light emitting diodes. This laser bandage may be worn by a patient and applied to a specific treatment area. The patient may wear the device for up to a week in between visits to their prescribing physician. At the end of the prescribed treatment length, the physician may re-program the device for a different treatment regimen, if desired. Alternatively, the physician may substitute the battery contained in the apparatus and continue said prescribed treatment regimen. The disclosed device is small enough to be worn under clothes so that it will not interfere with the patient's normal activities.
International Application WO2003/077996, published under the Patent Cooperation Treaty, pertains to a device and method for treatment of the external surfaces of a body by utilizing a light-emitting container. The device is comprised of a patch or bandage, applied on or adjacent to a specific external surface of a human or animal body part. This device then delivers light of varying intensity, wavelengths, duration. The exposure to this varying light is intended to treat fungi, among other things.
Review of Present Invention in Light of the Prior Art:
None of the art described above addresses all of the issues that the present invention does. The claimed invention includes a power source, at least one light emitting diode capable of generating light with wavelengths between about 800 nm and 980 nm, configurable printable circuit boards, and a chamber with a digit-receiving area. Studies have shown that flooding the treatment area with light having wavelengths at or about 870 nm and about 930 nm provides an adequate means for treatment. Optionally, the chamber can be equipped with an interchangeable bottom plate, and at least one additional light source capable of generating ultraviolet light.
The present invention provides for more complete exposure of the treatment area and adjacent tissues with NIR light than has previously been contemplated. The present invention uses both light emitting diodes capable of producing NIR and ultraviolet light. No other device in the prior art contains both of these features. The combination of these features allows for multiple users to use the same device shortly after each other without compromising patient safety and while maintaining sanitary conditions within the chamber of the invention.
When compared with other devices of the same nature, the present invention provides a chamber containing an area capable of receiving a user's digits, allowing the area to be treated to be fully exposed to the treating light emitted by both an array of light emitting diodes and the ultraviolet light emitting diode(s). For instance, if a user wanted to treat an infection of T. rubrum, the fungus most often responsible for athlete's foot, the user would place the foot into the digit receiving area of the invention. This user's foot would then be exposed to light from the array of light emitting diodes ranging from about 840 nm to about 980 nm as well as a dose of ultraviolet light, optimally at about 383 nm, which is used to primarily sterilize the device between treatments. Research from the University of Tokushima in Japan shows the sterilisation effects in both air and water at wavelengths of 365 nm and 385 nm. This exposure will result in killing the fungus without causing the user to feel any heat or discomfort. The fact that the user experiences no discomfort is an improvement over the prior art which generated an overabundance of heat in the user.
Another feature that differentiates the present invention is the configuration of the light emitting diodes. In a preferred embodiment, the light emitting diodes are arranged an array on the top of the chamber as well as embedded in posts to be inserted in between a user's digits. The posts are adjustable so that the distance between these posts can be appropriately configured to optimally treat the user's digit. As the posts are adjusted, the light emitting diodes should be able to fully illuminate the treatment area of the user. These adjustable columns are a significant departure from the prior art.
Thus, the present invention solves a number of issues that other devices in the field do not and as such it is novel and unique to the field.